<template>
  <div class="camera_outer">
    <video id="videoCamera" style="center" :width="videoWidth" :height="videoHeight" autoplay></video>
    <canvas style="display:none;" id="canvasCamera" :width="videoWidth" :height="videoHeight"></canvas>

    <div v-if="imgSrc" class="img_bg_camera">
      <img :src="imgSrc" alt class="tx_img" />
    </div>
    <button @click="setImage()">拍照</button>
    <button @click="handleUploadData()">上传</button>
  </div>
</template>
<script>
import axios from 'axios'
import {Message } from 'element-ui'
export default {
  data() {
    return {
      videoWidth: 500,
      videoHeight: 500,
      imgSrc: "",
      thisCancas: null,
      thisContext: null,
      thisVideo: null,
      userId: this.$route.params.id,
    };
  },
  mounted(){
    this.getCompetence()
  },
  beforeDestroy () {
    this.stopNavigator()
  },
  methods: {
    getCompetence() {
      var _this = this;
      this.thisCancas = document.getElementById("canvasCamera");
      this.thisContext = this.thisCancas.getContext("2d");
      this.thisVideo = document.getElementById("videoCamera");
      // 旧版本浏览器可能根本不支持mediaDevices，我们首先设置一个空对象
      if (navigator.mediaDevices === undefined) {
        navigator.mediaDevices = {};
      }
      // 一些浏览器实现了部分mediaDevices，我们不能只分配一个对象
      // 使用getUserMedia，因为它会覆盖现有的属性。
      // 这里，如果缺少getUserMedia属性，就添加它。
      if (navigator.mediaDevices.getUserMedia === undefined) {
        navigator.mediaDevices.getUserMedia = function (constraints) {
          // 首先获取现存的getUserMedia(如果存在)
          var getUserMedia =
            navigator.webkitGetUserMedia ||
            navigator.mozGetUserMedia ||
            navigator.getUserMedia;
          // 有些浏览器不支持，会返回错误信息
          // 保持接口一致
          if (!getUserMedia) {
            return Promise.reject(
              new Error("getUserMedia is not implemented in this browser")
            );
          }
          // 否则，使用Promise将调用包装到旧的navigator.getUserMedia
          return new Promise(function (resolve, reject) {
            getUserMedia.call(navigator, constraints, resolve, reject);
          });
        };
      }
      var constraints = {
        audio: false,
        video: {
          width: this.videoWidth,
          height: this.videoHeight,
          transform: "scaleX(-1)",
        },
      };
      navigator.mediaDevices
        .getUserMedia(constraints)
        .then(function (stream) {
          // 旧的浏览器可能没有srcObject
          if ("srcObject" in _this.thisVideo) {
            _this.thisVideo.srcObject = stream;
          } else {
            // 避免在新的浏览器中使用它，因为它正在被弃用。
            _this.thisVideo.src = window.URL.createObjectURL(stream);
          }
          _this.thisVideo.onloadedmetadata = function (e) {
            _this.thisVideo.play();
          };
        })
        .catch((err) => {
          console.log(err);
        });
    },
    // 绘制图片（拍照功能）
    setImage() {
      var _this = this;
      // 点击，canvas画图
      _this.thisContext.drawImage(
        _this.thisVideo,
        0,
        0,
        _this.videoWidth,
        _this.videoHeight
      );
      // 获取图片base64链接
      var image = this.thisCancas.toDataURL("image/png");
      _this.imgSrc = image;
      this.$emit("refreshDataList", this.imgSrc);
    },

    // base64转文件
    dataURLtoFile(dataurl, filename) {
      var arr = dataurl.split(",");
      var mime = arr[0].match(/:(.*?);/)[1];
      var bstr = atob(arr[1]);
      var n = bstr.length;
      var u8arr = new Uint8Array(n);
      while (n--) {
        u8arr[n] = bstr.charCodeAt(n);
      }
      return new File([u8arr], filename, { type: mime });
    },

    handleUploadData(){//已form提交
        if (this.imgSrc!==''){
          let file = this.imgSrc; // 把整个base64给file
          let type = "image/jpeg"; // 定义图片类型（canvas转的图片一般都是png，也可以指定其他类型）
          let time=(new Date()).valueOf();//生成时间戳
          let name = time + ".jpg"; // 定义文件名字（例如：abc.png ， cover.png）
          let conversions = this.dataURLtoFile(file, name); // 调用base64转图片方法
          let parms=new FormData();
          parms.append('file',conversions);
          let url='http://localhost:8222' + '/educenter/member/registerFace/' + this.userId;//你的接口
          axios.post(url,parms,{headers: {'Content-Type': 'multipart/form-data'}}).then(res=>{
            Message({
               message: res.data.message,
                type: 'success',
                duration: 1000
            })
            this.$router.push({path:"/login"})
          }).catch(err=>{
            this.$notify.error({
              title: '出现异常',
              message: err.msg
            });
          }).finally(()=>{
            stopNavigator()
          })
        }
      },

    // 关闭摄像头
    stopNavigator() {
      this.thisVideo.srcObject.getTracks()[0].stop();
    },
  },
};
</script>
